Identifying a user and/or verifying an identity claim of a user are important steps in ensuring the security of systems, networks, services and facilities, both for physical and for logical access. Furthermore, patterns of behavior or correlated information may also indicate security risks. Existing user identification/verification is often performed on the basis of a user's knowledge of a password or a personal identification number (PIN). Existing user identification/verification may also be performed on the basis of possession of a key or a card. Other existing identification/verification techniques include the use of a single biometric feature such as a voiceprint.
Accordingly, given the growing interest in security with respect to identification/verification and the deficiencies of existing identification/verification systems, there is a clear need for an improved security framework that provides a higher degree of efficiency and/or robustness and which not only can recognize individuals but also groups of individuals, together with the patterns in the meta-data that they jointly or individually generate.